The Skeletal System Chapter 6

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Integumentary System Test Results Oct 2016

Integumentary TEST Results Oct 2017

Action Plan – Letter to editor Deer hearts and kidneys CLA 6 Reading Guide due Wed 07 Nov Action Plan – Letter to editor Deer hearts and kidneys Flipped class bones notes as homework to study and Go over a little each day.

Skeletal System Consists of 206 bones and associated connective tissues including….. Cartilage Tendons Ligaments

Support Bones bear weight Cartilage is firm yet flexible 5 Functions of Bones Support Bones bear weight Cartilage is firm yet flexible Ligaments are bands of fibrous collagen tissue that hold bones together.

Ex: rib cage around heart Ex: skull around brain Function #2 2. Protection Surrounds organs Ex: rib cage around heart Ex: skull around brain

3. Movement Function #3 Tendons: muscle to bone Ligaments: allow limited movement between bones. Joints allow movement between bones Tendons and Ligaments mainly composed of collagen fibers.

Function #4 4. Storage Store calcium and phosphorus as calcium phosphate crystals – hydroxyapatite. Stores fat in bone cavities – yellow marrow Stores are released into blood when needed

Function #5 5. Blood cell production Red bone marrow forms blood cells and platelets. Mostly in spongy bone (epiphyses of long bone.)

Connective Tissue The skeletal system is made of connective tissue which contains extracellular matrices of: Collagen- a tough ropelike protein Proteoglycans- a large molecule with branches like pine branches Hydroxyapatite = calcium phosphate crystals

4 Types Based on Shape 1. Long Bones Most of the upper and lower limbs

2. Short Bones Ex: bones of the wrist and ankle 4 Types Based on Shape xxxxxxxxxxxxxxxxxxxxxxxx XXXXXXXX XXXXXXXXXXXXx

3.Flat Bones Ex: skull bones, ribs, scapulae, sternum 4 Types Based on Shape 3.Flat Bones Ex: skull bones, ribs, scapulae, sternum

4 Types Based on Shape 4. Irregular Bones Ex: Vertebrae, facial bones

Long Bone Structure Diaphysis central shaft

Long Bone Structure Epiphyses Each end is called an epiphysis. Two ends Each end is called an epiphysis.

Long Bone Structure Articular Cartilage – Covers ends of epiphyses where bone moves with other bone. Made up of what type of cartilage? Hyaline!

Long Bone Structure Epiphyseal line- Replaces cartilage of the epiphyseal growth plate

Long Bone Structure Medullary cavity large cavity in the diaphysis contains marrow

Long Bone Structure Yellow marrow consists mostly of fat replaces red marrow in adults

Using a clean piece of 8 ½” x 11” printer paper, SKETCH and LABEL at least 10 different components of bone in 12 minutes. 30 points good effort credit. Use the class set textbook (5th edition) on page 118 to free hand sketch one or more of the diagrams in figure 6.2 (or use page 180 of your newer textbook 9th edition.) Or use page 81 of the “lab-exercise” manual.

Page 198 Review Questions: Which of these is not a function of bone? a. internal support and protection b. attachment for the muscles c. Calcium and phosphate storage d. blood cell production e. vitamin D storage “E.” is not a function of bone. 2. Chondrocytes are mature cartilage cells within the ________, and they are derived from _______. a. perichondrium, fibroblasts b. perichondrium, chondroblasts c. lacunae, fibroblasts d. lacunae, chondroblasts d. lacunae, chondroblasts 3. Which of these statements concerning cartilage is correct? a. Cartilage often occurs in thin plates or sheets. b. Chondrocytes receive nutrients & oxygen from blood vessels in the matrix. c. Articular cartilage has a thick perichondrium layer. d. The perichondrium contains both chondrocytes and osteocytes. e. Appositional growth of cartilage occurs when chondrocytes within the tissue add more matric from the inside. A. cartilage occurs in thin sheets as put on by chondroblasts.

4. Which of these substances makes up the major portion of bone? a. collagen b. proteoglycan aggregates c. hydroxyapatite d. osteoblasts e. osteocytes hydroxyapatite 5. The flexible strength of bones occurs because of: Collagen 6. The primary function of osteoclasts is to: a. prevent osteoblasts from forming. b. become osteocytes c. break down bone. d. secrete calcium salts and collagen fibers. e. form the periosteum C. Break down bone

7. Central canals: A. connect perforating canals to canaliculi B. connect spongy bone to compact bone. C. are where blood cells are produced D. are found only in spongy bones. E. are lined with periosteum. 7 = A. connects blood to canaliculi 8. The lamellae found in osteons are _________lamellae. a. circumferential b. concentric c. interstitial Concentric rings of lamellae 9. Spongy bones consists of interconnecting rods or plates of bone called: a. osteosns b. canaliculi c. circumferential lamellae d. haversian system e. trabeculae Trabeculae! 10. A fracture in the shaft of a bone is a break in the: a. epiphysis b. perichondrium c. diaphysis d. articular cartilage e. sacroiliac C. Diaphysis = shaft

11. Yellow marrow is: A. found mostly in children’s bones. B. found in the epiphyseal plate. C. Important for blood cell production. D. mostly adipose tissue. E. where blood cells are mainly produced. D. Fat = adipose tissue 12. The periosteum: A. is an epithelial tissue membrane. B. covers the outer and internal surfaces of bone. C. contains only osteoblasts. D. becomes continuous with collagen fibers of tendons or ligaments. E. has a single fibrous layer Tendons and ligaments are an extension of periosteum.

Perform case study with a partner, prepare to discuss Critical Thinking #3 Astronauts can experience a dramatic decrease in bone density while in a weightless environment. Explain how this happens and suggest a way to slow the loss of bone tissue. Perform case study with a partner, prepare to discuss as a class in 20 minutes.

Case Study link to compare with your group answers: http://www.mhhe.com/biosci/ap/ap_casestudies/cases/ap_case06.html It is good to understand and follow the questions associated with this case study, especially question #6.

Periosteum Long Bone Structure covers outer surface of bone. dense connective tissue. contains blood vessels, nerves, osteoclasts, & osteoblasts.

Long Bone Structure Endosteum lines surface of medullary cavity thin connective tissue membrane contains osteoblasts

Compound Fracture

2 types of bone based on structure: Compact bone Cancellous bone C

Osteon or (haversian system) – basic unit of structure of compact bone

Osteon or (haversian system) – basic unit of structure of compact bone.

Osteon Consists of rings of lamellae

Lamellae – thin sheets of extracellular matrix

Osteocytes – bone cells located between the lamellae in spaces called lacunae

osteocyte

Practice labeling 1. Periosteum 2. Medullary cavity 3. Compact bone 4. Cancellous bone 5. Epiphyseal plate 6. Epiphysis 7. Osteon 8. Perforating canal 9. Endosteum 10. Canaliculi 11. Osteocyte Diaphysis Lacuna Practice labeling

Canaliculi – channels running within the lamellae between the osteocytes

Caniculi

Canaliculi Pathway for nutrients from blood vessels of central canals to ostocytes Looks like cracks in the lamellae Waste products diffuse through them

Cancellous bone Spongy bone Located in epiphyses of long bone and interior of other bones Consists of trabeculae

Trabeculae Interconnecting rods or plates of bone Add strength Spaces filled with marrow Consists of lamellae with osteocytes

Six Bone Features to know: 1. Foramen - “Hole” in a bone.

2. Fossa - A “depression” or dip in a bone. 3. Condyle - Smooth, rounded end of a bone where it articulates with another bone, or bones.

Xiphoid process of sternum <------- 4. Process - A “projection” from a bone. Xiphoid process of sternum <-------

5. Tubercle (tuberosity) - A “lump” or bump on a bone.

6. Canal or Meatus - Tunnel or canal through the bone.

Read and Chapter 6 and your CLA packet, as well as these notes.